This is the same physical aperture as the F25SRF2 aperture and has become available for use with the FUV-MAMA detector to minimize the contribution from the dark current when observing very faint targets. This aperture moves the target 2 arcseconds above the bottom edge of the FUV-MAMA. It is yet to be determined if the throughput for a target at this position is significantly different from that obtained at the standard position.